Novel Panel of Long Noncoding RNAs as Diagnostic Biomarkers for Amnestic Mild Cognitive Impairment in Peripheral Blood

Background: Long noncoding RNAs (lncRNAs) regulate the pathogenesis of Alzheimer's disease (AD). Objective: To identify lncRNAs in the peripheral blood as potential diagnostic biomarkers for amnestic mild cognitive impairment. Methods: In the discovery group, a microarray was used to screen for significant differences in lncRNA expression between patients with mild cognitive impairment (MCI) caused byADand normal controls (NCs) (n = 10; MCI, 5; NC, 5). Furthermore, two analytic groups were assessed (analytic group 1: n = 10; amnestic MCI (aMCI), 5; NC, 5; analytic group 2: n = 30; AD, 10; aMCI, 10; NC, 10) and finalized in the validation group (n = 150; AD, 50; aMCI, 50; NC, 50). In the analytic and validation groups, real-time quantitative reverse-transcription polymerase chain reaction was used to identify differentially expressed lncRNAs between the aMCI and NC groups. Results: We identified 67 upregulated and 220 downregulated lncRNAs among the expression profiles. The panel with lncRNAs T324988, NR 024049, ENST00000567919, and ENST00000549762 displayed the highest discrimination ability between patients with aMCI and NCs. The area under the receiver operating characteristic curve of this combined model was 0.941, with a sensitivity of 92.00% and specificity of 84.00%. Conclusions: This study reports on a panel of four lncRNAs as promising biomarkers to diagnose aMCIs.